Hydrogenated furfuryl alcohol partial polymers



ug- 21, 1951 A. P. DUNLOP Erm. 2,564,835

HYDROGENATED FURFURYL ALCOHOL PARTIAL POLYMERS v Filed May 4, 1949 Y Furfuryl Alcohol Polymerization l Disiil'laiion r-I-i 1 Furfurylu .o Polymers Alcohol Hydrogenoton l Disll'lo'ron 'L-j y Use os vvis Telrahydro- Polymers furfuryl Alcohol Polymer Fractions Inventors: Andrew P.' Dunlop and Poul R.Stoul nBy.-

Aghenl Patented Aug. 21, 1951 HYDRQGENATEII ALCOHOL' PARTIAE POIYME-RS* Andrew.v P.: DunlopiRiversidaandf PauLR. Stout,v Chicagmz IlLkv assignors to-The Quaker Oats Company, Chicago, Ill.a..corporation of NewA Jersey AppIicatiorrMay; 4 1949,` S'era'lNo.- 91,316

(Cl. MWF-8.8.5).

llll. GlafimSi Thisinvention relates to`v hydrogenated. fur-v` f-urylalcohol partial polymers and Ito' the methodsy of preparing the same. These hydrogenated; polymers are especially/adapted for usefinf-thef preparation ofnevvV synthetic resinousrcompositions and they` arealso-usefu'l as plasti'cizers .par-1 ticularly as plasticizerspfonfuran and vinyl type resinsv with which they are compatible. As used herein the term furanresins appliessto: resins derivedfrom furancompounds and' isnotto be limitedA to Y resins derivedffromiu-ran itself'.

Certain resins or polymers preparedy from furans and from vinyl compoundsV possess manyv desirable propertiesincluding rImechanicall strength and'chemical resistance; however; with age they tend to become brittle.v To overcome` this latter deficiency certainconstituents calledl plasticizersare added.` Many7V of Vthese p lasticizers4 are costly, are di'icultto incorporateinto'the composition by milling-because of incompatibility with the resin. and in addition, some require a more or lessy extended'aging period forrtheV de: velopmentof maximum plasticity. Others; even; though they are sufficiently compatible initially; with the resin givingwrise; tof,improvedcelasticity; are not suitable since the ^improvement obtained' is lostwhen the resin is converted'intoitsnal' state. This causesthev components of the mixture to separate With consequent impairment of elastic properties...

It is an object of the present' invention to provide a new class of plasticizers for furan resins and vinyl type resins whichplasticizers are effective while at the same timer-they avoid the principal objections to the plasticizers previously available.

These and other objects are obtained by preparing plasticizers comprising hydrogenating, either completely or incompletely, a partiallypolymerizedfurfuryl. alcohol. The partially. D015@ merized furfuryl alcohol` used inthepresent` inf'v vention. isa partially resinied'furfluryl alcohol of any desired viscosity-short ofthegelstagesand may be prepared by` any of) the knownmethods;l however., we. preferA the methods describeldlinour co,pending application, Serial' No. v758,503."leltl` July 2, 1947.

Partial resiniflcation ofV furfuryl-alcohoh asis well known, may be. effected by heatlalone, cata-- lysts alone, or by heat and catalysts.` Suitable. catalysts which may be usedI are mineral acids,Iv organic carboxylic acids and sulfonic acids,A acidic! salts, or nely divided metals. vSpecific examples. of suitable catalysts are: phosphoric acid, sulfuric. acid, oxalic acid, paratoluenesulfonic. acid,l cal.-

2. cumchloride,-. ferrie chloride, boron fluoride.-k iodine, etc.. During; resinication the furfurylalcohol undergoes chemical and physicalfchan ges` to.H yield az mixture.-y of fusible.. condensation products..

Partialfresinicationof furfuryl alcohol. as de.-` scribedzabovezis carried out. until the resulting` resinous; product .has the. desired viscosity. For exam-ple;l a. suitable,` partially. resinifed, furfuryl alcohol; resinA formed-by heat alone isobtained byy kreluxling,` furfuryl alcoholto. al :viscous resin having, for. example, a; viscosityV of. ab .ui'.100r centrpoisesat 25? G.` Afsuitable partially-resina? lied furfurylalcoholf-resin.. formed; by the. aid.. ofi a. catalystfis l obtainediby 'heating -furfuryl alcohol-ini an. open vessel in the., presencen of` phosphoric; acid to a .viscous resin having,` for.- exam-ple;v a viscosity. of l about .'2-,000--centipoisesr al'f;.25,"V Q. A: suitable partially resinied-.furfuryl; alcohol resin may be formed bythe. use fof; aacatalyst alone i by` adding boron;l fluoride, dissolved in methanol to furfuryl. alcol'iolvthen` allowingfthe; resulting; mixture tof stand;V at about 20d-1G.. untila viscousfresin. having-for example, a: vis.cosity of :about 1,000 centipoiseszat 25.?` C.. is. obtained;A When a resin ofthe-desired viscosity-.isgobtainedfthe;` catalyst is l neutralized-.with e sodiumA` hydroxide-.vn y

Wehave'found thats these-resins when; hydravgenated produce plasticizersfWhChcpOSsess; many desirable; C Lrialties` including;y compatibility'- with iuran resns.z..vinylftimeqresins.andiotheizgresinss andlthey-.have ai 10W/ melting point., General-ly;v theyaregliquid or sof-t at lovntemperatures render:-VY ingfgthenrgcapable fof being; worked Viii-to 'rr-resins fat; ordinarystemperatureswith conventionabapnarae: tusxandtthey psessa lovv.-Y vapor lpressure.:`

In carrying out the presenilzfnvention .pantiallyg polymerized furfuryl alcoholvprepared according to the method describedlinhour co-pending app1ieation-, .or=..by any. other. suitable. meansis hydrogenatedlin the.. presence of la.. catalyst., Ria-neynickebplatinum, or. palladium, are .suit` able.. Ii..desire d thehydrogenation may; baconducted inthe presenceot a-suitablesolvent. Fol, lowing.- hydrogenatiom, the product. and catalyst mayzbe separated byevilltratiorn.,centrifugation or. dopant;ationL and.A anyK solvent used. removed.' evaporation` ordistillation;

When; `furfuryl alcohol .isf-partially. polymerized a. complex :mixture consistingoff: unchangedfiuw furyL alcohol. dimer; trimer:V andiv highecpolyf merio, forms-off furfuryl `alcohol is--,obtained.y v It a. product-ot` a more or lesssdeinite-fmolecu-lan szeis desired thefmixtureof polymersobtainedfin desirable. As one example, such a plasticizer is preferred when used in thin films thus avoiding execessive losses therefrom through evaporation. In addition to separating the mixture into fractions according to molecular size we have found it possible to prepare a colorless or nearly colorless plasticizer by a process involving fractionalv distillation. For best results the mixture should be distilled under vacuum. The distillate soI obtained is hydrogenated and then redistilled under vacuum. If a small amount of color can be tolerated the first distillation step may be eliminated. f

The figure is a flow sheet of the polymerization-hydrogenation process. An inspection of this diagram discloses that the process may be varied in that the polymerized product may be hydrogenated immediately after polymerization and then distilled or the distillation may precede the hydrogenation step. For practical reasons, the latter method is preferred because the removal of unchanged furfuryl alcohol from the mixture permits the hydrogenation of a greater quantity of partial polymer per charge and the recovered furfuryl alcohol can be returned to the polymerization step. Furthermore, if this furfuryl-alcohol is not removed it will be reduced to tetrahydrofurfuryl alcohol during the hydrogenation step and since for most purposes a hydrogenated polymer free of tetrahydrofurfuryl alcohol is preferable, distillation will be necessary eventually. y

The plasticizers of the present invention are especially effective when used with furan resins, vinyl type resins, etc. The amount of the plasticizer used may vary Widely being generally between about 5% or even less to about 50% based upon the Weight of the resin and will be governed by the properties desired to be imparted to the resinous compositions.

In order to disclose the nature of the present invention still more clearly, the following illustrative examples Will be given. It is to be understood that the invention is not to be limited to the specific conditions or details set forth in these examples except insofar as such limitations are specified in the appended claims. Parts given are parts by Weight. y

Example 1 A mixture of 347 parts of a furfuryl alcohol acid-catalyzed partial polymer, the pH of which had been adjusted to 8 with sodium hydroxide and having a viscosity of about 2000 centipoises at 25 C., 52 parts of Raney nickel catalyst and 152 parts of isopropyl alcohol was hydrogenated at 19o-205 C. and a pressure of 1000-1'700 pounds per square inch. 13.6 parts of hydrogen was taken up in 41/2 hours. Since the starting material contained 17% water, this represented hydrogenation of somewhat less than 85% of the furanoid unsaturation originally present in the polymer. After removing the catalyst by filtration and the solvent by vacuum distillation, a liquid was recovered which had a viscosity approximately equal to that of the starting material and possessed a green-red dichroism.

Example 2 A mixture of 303 parts of a furfuryl alcohol acid-catalyzed polymer having a pH of 6.3, moisture 6% and a viscosity of about 1300 centipoises at 25 C., 30 parts of Raney nickel catalyst and 280 parts of isopropyl alcohol was hydrogenated at -225 C. and a pressure of 1400-1600 pounds per square inch. 5.8 parts of hydrogen was taken up Aintwo hours which represented hydrogenation of somewhat less than 49 percent of the furanoid unsaturation originally present in the polymer.

I Example 3 In this example various mixtures which had been prepared containing l'l-'lO percent of the hydrogenated product of Example 1 and the remainder being the starting material of Example 1 were cured at1180 C. in the absence of any added catalyst. The flexibility of the cured product varied directly with the amount of hydrogenated product added. All cured samples were insoluble in cold aqueous sodium hydroxide, ethyl ether and carbon tetrachloride.

VEzzcample 4 Example 5 A portion of the product of Example 1 was distilled under vacuum to give 65 percent distillate and still bottoms of 35 percent. The distillate was then fractionally distilled under a vacuum (4 mm. pressure) giving 26 percent tetrahydrofurfuryl alcohol and the following fractions:

Boiling Yield m Pgismlam fao-9o 1 25-150 14 15H8() s iso-20o 12 20H20 s 22o-245 8 We have found that improved resins may be obtained by condensing an incompletely hydrogenated partially-resinified-furfuryl alcohol with itself or with a thermoplastic resin such as those derived from the following products: furfuryl alcohol, furfuryl alcohol-dimethylolurea, furfuryl alcohol-phenol-formaldehyde, furfuryl alcohol-melamine-aldehyde, furfuryl alcohol-ammonium thiocyanate-aldehyde, alkylfurans, unsaturated furyl aldehydes, furfural-phenol7 vinyl type compounds, ureaformaldehyde, malamineformaldehyde, etc. This condensation can be effected by the use of heat alone, an acidic catalyst alone or by heat and an acidic catalyst. The resultant resins combine strength, toughness, elasticity, fiexibility, adhesiveness, and high chemical resistance with excellent4 insulating properties which are highly desirable in compositions used as insulating enamel's for coating electrical conductors. As an example a wire enamel may be prepared consisting of an incompletely hydrogenated partially resinied furfuryl alcohol, a fatty acid modied alkyd resin such as glyceryl phthalate modified with linseed fatty acids and a suitable solvent such as acetone, ethyl acetate, benzene, etc. A typical formulation is as follows: hydrogenated furfuryl alcohol polymer 1 part, modified alkyd resin 1 part, and acetone- 2 parts. The nature of this condensation reaction is rather obscure .but a theory of` explanations is.V as. follows: an incompletely hydrogenatedpartial' polymer will possess unsaturated bonds and because of those bonds the polymer can condense with itself or copolymerize through cross linkage with other polymerizable resins particularly furan resins.

Example 6 A mixture oi 773 parts of a furfuryl alcohol acid-catalyzed partial polymer which had been neutralized, dehydrated under vacuum, and having a viscosity of about 2000 centipoises at 25 `C., 80 parts of Raney nickel catalyst and 20 parts of isopropyl alcohol was hydrogenated at 17o-200 C. and a pressure of 1000-1800 pounds per square inch. 8.6 parts of hydrogen was taken up in 6 hours which was suicient to hydrogenate about 25 percent of the furanoid unsaturation originally present in the polymer.

Example 7 Since the stroke cure is a measure of the thermo-setting properties of a resin, the following resins were so tested: An acid-catalyzed furfuryl alcohol partial polymer having a viscosity of about 2000 centipoises of 25 C., resin of Example 6 and the resin of Example 4. The stroke cure has been delined as the time in seconds required for a resin to convert from a fusible orliquid condition at a definite temperature while being stroked with a spatula to a conditionat which the spatula either no longer sticks to the resin or slides over it with relative ease. In practice aboutI 2 cc. of the resin is placed on a hot plate, the temperature of which is adjusted to 145- 150 C., and stroked approximately 90-100 strokes per minute) with the flat side of a spatula to smooth the resin into a square 2 to 3 inches on a side.

None of the foregoing resins gave a stroke cure in ten minutes in the absence of a catalyst and in addition it was impossible to obtain a stroke cure in ten minutes on the resin of Example 4 in the presence of a catalyst. The stroke cures obtained on the resins in the presence of a catalyst are summarized below.

These hydrogenated furfuryl alcohol partial polymers are also elective to impart increased flexibility and adherence to other resins, e. g., a furfurylated dimethylolurea resin such as described in @ample 1 of the Dunlop copending application Serial Number 586,631. filed April 4, 12945;. and` a. iurfural-phenol; resinsuch: as prepared.Y according to the. method. described. in U. S. Patent 1,969,890. In theseztests,.a mixture consisting. of. 1 part of resin Example; 6, lipari; turfurylated dimethylolurea resinand 0.02 part phosphoric; acid was heated'ior 1- hour at.` 160o C. Inanothertest, a mixture consisting off 1' part of; resin Example 6,1 1; partoi", furfuralphenol resin and 0.02 part. phosphoric; acid; was heated for 1 hour at 160 C. In both examples, the resulting', resins possessed good adhesion,` toughnesaviiexibility and. resistance to; sol-vents;

The resins of Example 4 and Example 6 were added to the resinous materials listed below to determine their compatibility with those resins. In these tests equal quantities of the hydrogenated furfuryl alcohol polymer and the resinous material were mixed and gently heated. The following resinous materials were found to be compatible with both hydrogenated polymers: cellulose acetate-butyrate, cellulose nitrate, ethyl cellulose, furfural-phenol resin of Example 8, furfuryl alcohol-ammonium thiocyanate prepared according to Example 2 of the U. S. Patent 2,368,426, furfurylated dimethylolurea of Example 8, methylfuran polymer prepared according to Example 5 of our copending application Serial Number 621,592 led October 10, 1945, now Patent 2,486,392, granted November 1, 1949, methyl methacrylate, phenol-formaldehyde laminating varnish, vinyl acetate and vinyl butyral. Resinous materials such as cellulose acetate, nylon, styrene, vinyl chloride, vinyl chloride-acetate and vinyl-vinylidene chloride exhibited only limited compatibility with the hydrogenated polymers. Polyethylene is an example of a resinous material which is incompatible with the hydrogenated polymers.

Having now described and illustrated our invention, we wish it to be understood that our invention is not to be limited to the specic details herein described, except insofar as such limitations are specied in the appended claims.

We claim:

1. A process of producing a composition of matter which comprises the hydrogenation` of a partially resiniiied furfuryl alcohol.

2. A process of producing a composition of matter which comprises the hydrogenation of an acidcatalyzed partially resinii'led furfuryl alcohol.

3. A process of producing a composition of matter which comprises the hydr-ogenation of a partially resiniiied furfuryl alcohol at a temperature of 1'70-225" C. and a pressure of 1000-1800 pounds per square inch.

4. A process of producing a new thermosetting artiiicial resin which comprises heating an incompletely hydrogenated partially resiniediurfuryl alcohol.

5. A process of producing a new thermosetting articial resin which comprises heating an incompletely hydrogenated partially resinied furfuryl alcohol in the presence of an acidic catalyst.

6. A process of producing a new plasticizer which comprises the hydrogenation of a liquid partially resinified furfuryl alcohol.

7. As a composition oi matter a partially polymerized furfuryl alcohol having a viscosity of 10D-80,000 centipoises at 25 C. and wherein at least 25 per cent of the unsaturation of said partially polymerized furfurylv alcohol has been vsaturated with hydrogen.

8. As a composition of matter a partially polymerized furfuryl alcohol having a viscosity of 7 1D0-80,000 centipoises at 25 C. and wherein 25 `to 85 per cent of the unsaturation of said parto 85 per cent of the unsaturationof said partially polymerized furfuryl alcohol has been saturated with hydrogen.

ANDREW P. DUNLOP. PAUL R. STOUT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,780,652 Lawson Nov. 4, 1930 2,345,966 Fielder Apr. 4, 1944 

7. AS A COMPOSITION OF MATTER A PARTIALLY POLYMERIZED FURFURYL ALCOHOL HAVING A VISCOSITY OF 100-80,000 CENTIPOISES AT 25* C. AND WHEREIN AT LEAST 25 PER CENT OF THE UNSATURATION OF SAID PAR- 